Phenomenological features of auditory hallucinations and their symptomatological relevance.

Auditory hallucinations include particularly diverse phenomena that reflect various mental functions and pathologies. Their assessment may provide valuable clinical information. This article describes the development of the Matsuzawa Assessment Schedule for Auditory Hallucination (MASAH), which was designed to obtain a broadened view of the phenomena by investigating a wide range of their characteristics. The aim was to identify the basic phenomenological features of auditory hallucinations by performing a factor analytic study of the MASAH ratings of 214 patients with schizophrenia or schizoaffective disorder. Four identified factors were intractability, delusion, influence, and externality, on the basis of which we constructed composite scales that were assumed to represent the features. The correlation analysis of the scales with symptom dimensions derived from the positive and negative syndrome scale verified their clinical relevance. They were also interpretable in terms of human responses to the abnormal experience and some symptom constructs such as delusion and influence experience. It is concluded that the MASAH is an efficient means for evaluating the features, and that this study elicited new understandings of the phenomena such as their multifarious composition and contiguities with other psychotic symptoms.